My nephew, 52 yrs old, has flu. He also has hepatitis-c at about 3.7. His temp is 103.4 (the high). Average has been about 102.4. What can he take 4 fever?

Tylenol (acetaminophen) Even with liver disease from hep c, tylenol (acetaminophen) can be taken for things like a fever. I would just keep it to < than 2gm/day.
Tylenol (acetaminophen) or nsaid. Assume he is not in liver failure or on transplant list low dose tylenol (acetaminophen) (less than 2 grams a day usual dose allowed in 4 grams a day) is safe also motrin/aleve (NSAID) type product is safe would consider alternating between the two every 4 hours or so this is with a confirmed diagnosis of flu if not confirmed diagnosis would seek medical attention.